Yamawaki Hamono (Gou Umanosuke Yoshihiro) 山脇刃物製作所（郷右馬允義弘）

Marks on the blade

About

Sakai wholesaler whose brand is 郷右馬允義弘 (Gou Umanosuke Yoshihiro), usually shortened to 義弘 Yoshihiro on the blade. Not the same as 'Yoshihiro Cutlery' (a US retailer brand) — a frequent mix-up.

Steels

• Shirogami #2 (White #2) — Hitachi/Proterial Yasuki carbon steel. Easiest to sharpen, takes the finest edge, rusts fast.
• Aogami #2 (Blue #2) — White #2 plus chromium and tungsten: better wear resistance, a touch harder to sharpen.
• Ginsan (Silver #3, Gingami 3) — Hitachi/Proterial stainless that sharpens almost like White steel: the usual 'stainless wa-bocho' steel in Sakai, and the Hatsukokoro Ginrei line.
• Molybdenum-vanadium stainless — Workhorse stainless in Brieto professional knives and household lines from Tsubame factories.

Facts

Knife types made

• Yanagiba 柳刃 · Slicing sashimi and sushi toppings in one pull stroke.
• Deba 出刃 · Breaking down whole fish: heads, bones, filleting. Thick spine.
• Usuba 薄刃 · Professional vegetable knife for katsuramuki (rotary peeling) and decorative cuts.
• Gyuto (chef's knife) 牛刀 · Western-style chef's knife: meat, large vegetables, rocking cuts.
• Santoku 三徳 · All-round home knife: vegetables, fish, meat. The first knife to buy.
• Petty ペティ · Small jobs in hand: peeling, trimming, garnish, fruit.

Care for these steels

Carbon steel (Shirogami / Aogami / SK)

• Rinse and wipe dry immediately after each use — never leave it wet or in the sink.
• Do not put in the dishwasher. Do not cut acidic foods and walk away (lemon, tomato, onion will stain within minutes).
• A grey-blue patina is normal and protective; orange rust is not. Remove orange rust with a rust eraser or #1000 stone slurry.
• Before storing for more than a day, wipe with camellia oil (椿油) or any food-safe oil.
• Store dry, in a saya or on a rack — not loose in a drawer.

Stainless (VG10 / AUS10 / molybdenum / CROMOVA / SG2)

• Wipe dry after use. Dishwasher still not recommended — the heat and detergent dull the edge and loosen handles.
• Powder steels (SG2) chip rather than roll: avoid bones, frozen food and twisting cuts.
• Sharpen on #1000; finish on #3000–5000 if you like a polished edge.

Where to buy

Maker websiteeBay (new & used) affiliateAmazon US affiliateAmazon JP affiliate